//
//  UIButton+WLContentExtention.m
//  WLForm
//
//  Created by 刘光强 on 2018/5/4.
//  Copyright © 2018年 quangqiang. All rights reserved.
//

#import "UIButton+MHContentExtention.h"

@implementation UIButton (MHContentExtention)

- (void)layoutButtonWithEdgeInsetsStyle:(MKButtonEdgeInsetsStyle)style
                        imageTitleSpace:(CGFloat)space {
    /**
     * titleEdgeInsets是title相对于其上下左右的inset，跟tableView的contentInset是类似的，
     * 如果只有title，那它上下左右都是相对于button的，image也是一样；
     * 如果同时有image和label，那这时候image的上左下是相对于button，右边是相对于label的；title的上右下是相对于button，左边是相对于image的。
     */

    // 得到imageView和titleLabel的宽、高
    CGFloat imageWith = self.imageView.frame.size.width;
    CGFloat imageHeight = self.imageView.frame.size.height;
    
    CGFloat labelWidth = 0.0;
    CGFloat labelHeight = 0.0;
    
    if ([UIDevice currentDevice].systemVersion.floatValue >= 8.0) {
        // 由于iOS8中titleLabel的size为0，用下面的这种设置
        labelWidth = self.titleLabel.intrinsicContentSize.width;
        labelHeight = self.titleLabel.intrinsicContentSize.height;
    } else {
        labelWidth = self.titleLabel.frame.size.width;
        labelHeight = self.titleLabel.frame.size.height;
    }
    
    // 声明全局的imageEdgeInsets和labelEdgeInsets
    UIEdgeInsets imageEdgeInsets = UIEdgeInsetsZero;
    UIEdgeInsets labelEdgeInsets = UIEdgeInsetsZero;
    
    // 根据style和space得到imageEdgeInsets和labelEdgeInsets的值
    switch (style) {
        case MKButtonEdgeInsetsStyleTop: {
            imageEdgeInsets = UIEdgeInsetsMake(-labelHeight - space / 2.0, 0, 0, -labelWidth);
            labelEdgeInsets = UIEdgeInsetsMake(0, -imageWith, -imageHeight - space / 2.0, 0);
        }
        break;
        case MKButtonEdgeInsetsStyleLeft: {
            imageEdgeInsets = UIEdgeInsetsMake(0, -space / 2.0, 0, space / 2.0);
            labelEdgeInsets = UIEdgeInsetsMake(0, space / 2.0, 0, -space / 2.0);
        }
        break;
        case MKButtonEdgeInsetsStyleBottom: {
            imageEdgeInsets = UIEdgeInsetsMake(0, 0, -labelHeight - space / 2.0, -labelWidth);
            labelEdgeInsets = UIEdgeInsetsMake(-imageHeight - space / 2.0, -imageWith, 0, 0);
        }
        break;
        case MKButtonEdgeInsetsStyleRight: {
            imageEdgeInsets = UIEdgeInsetsMake(0, labelWidth + space / 2.0, 0, -labelWidth - space / 2.0);
            labelEdgeInsets = UIEdgeInsetsMake(0, -imageWith - space / 2.0, 0, imageWith+space / 2.0);
        }
        break;
    }
    
    // 赋值
    self.titleEdgeInsets = labelEdgeInsets;
    self.imageEdgeInsets = imageEdgeInsets;
}
@end
